Explanation/Reference:
Azure Event Hubs Dedicated is ideal for customers that need a single-tenant deployment to manage the most demanding requirements.
Note: The dedicated tier option involves Zero maintenance: The service manages load balancing, OS updates, security patches, and partitioning.
The following table compares the available service tiers of Event Hubs. The Event Hubs Dedicated offering is a fixed monthly price, compared to usage pricing for most features of Standard. The Dedicated tier offers all the features of the Standard plan, but with enterprise scale capacity for customers with demanding workloads.

Reference: https://docs.microsoft.com/en-us/azure/event-hubs/event-hubs-dedicated-overview